STUBBORNESS IS A SIN?

Stubbornness can be a sin, why? because you are doing something that you know will harm yourself or someone else by doing it. In this case someone I love is disregarding advice and doing what they want anyway. For example my mother-in-law just had a heart attack one week ago. The Doctor told her take it easy for a few weeks stay away from the public, now if she disregards this she is doing what she wants and could bring on another heart attack. This is willful sin. And a sin none the less because she is disregarding sound medical advice. But if she obeys and does what she's told she'll make a full recovery. That's what being stubborn does. You do what you want and have no care for what might happen therefore causing others to reap the problems that stubbornness causes. If someone reads this and has a scripture to help me out I'd appreciate it because the person being stubborn is a christian and disagrees with what I'm trying to get across that being whether it's God or man if you don't follow good sound advice it's sin.